Duplicate date datas (rows) from the view

Question

Hi friends,
My purpose is to get the duplicate date datas from the view.
The following select (1) works well (according to the employee_id). But, the select (2) doesn't work when want to get the duplicate date datas from the view and it gives me an error such as: ORA-00979: not a GROUP BY expression.
Can you please help... Thanks in advance!
--- 1 ---
SELECT   id,
           state,
           insert_timestamp,
           update_timestamp,
           update_status,
           staff_including_date,
           company_name,
           position,
           position_name,
           release_date,
           notes,
           update_user_id,
           employee_id,
           fk_org_structure_id,
           fk_staff_position_id,
           fk_document_id,
           document_date,
           document_number,
           d_order_date,
           fk_activity_operation_type,
           activity_operation_name,
           fk_military_type,
           military_type_name,
           fk_activity_type,
           activity_type_name
    FROM   fhn_staff.v_fs_labor_activity
   WHERE   employee_id = :p_employee_id AND state = 1
ORDER BY   fk_activity_type, staff_including_date, id;--- 2 ---
SELECT id,
         state,
         insert_timestamp,
         update_timestamp,
         update_status,
         staff_including_date, COUNT (staff_including_date),
         company_name,
         position,
         position_name,
         release_date,
         notes,
         update_user_id,
         employee_id,
         fk_org_structure_id,
         fk_staff_position_id,
         fk_document_id,
         document_date,
         document_number,
         d_order_date,
         fk_activity_operation_type,
         activity_operation_name,
         fk_military_type,
         military_type_name,
         fk_activity_type,
         activity_type_name
    FROM fhn_staff.v_fs_labor_activity
   WHERE state = 1
GROUP BY staff_including_date
  HAVING COUNT (staff_including_date) > 1
ORDER BY fk_activity_type, staff_including_date, id;

Answer 1

The first four columns? What about the other ones as well.
If you to fetch a different set of columns than you want to group on, then you should look at an analytic function, i.e
COUNT(*) OVER (PARTITION BY... )Assuming that you do only want to group by the date (seems a bit odd but I know nothing about what you're trying to do with your data), then it sould be something like this:
SELECT *
FROM (
SELECT id,
         state,
         insert_timestamp,
         update_timestamp,
         update_status,
         staff_including_date, COUNT (*) OVER (PARTITION BY staff_including_date) cnt,
         company_name,
         position,
         position_name,
         release_date,
         notes,
         update_user_id,
         employee_id,
         fk_org_structure_id,
         fk_staff_position_id,
         fk_document_id,
         document_date,
         document_number,
         d_order_date,
         fk_activity_operation_type,
         activity_operation_name,
         fk_military_type,
         military_type_name,
         fk_activity_type,
         activity_type_name
    FROM fhn_staff.v_fs_labor_activity
   WHERE state = 1)
WHERE cnt  > 1
ORDER BY fk_activity_type, staff_including_date, id;